PT-2026-36918 · Unknown · Wifi Extender Wdr201A

Daniele Berardinelli + 1 · Published 2026-05-04 · Updated 2026-05-05 · CVE-2026-41927

Positive Technologies (AI Summary)

CVSS v4.0

8.3

High

Base vector

AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Name of the Vulnerable Software and Affected Versions WDR201A WiFi Extender HW V2.1, FW LFMZX28040922V1.02

Description A stack-based buffer overflow exists in the 'firewall.cgi' and 'makeRequest.cgi' binaries. Unauthenticated attackers can overwrite the saved return address by sending a POST request with a Content-Length header exceeding 512 bytes. This is caused by insufficient length validation in the fgets() function, which can lead to arbitrary code execution using return-oriented programming or return-to-libc techniques.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

Stack Overflow

Weakness Enumeration

CWE-121

Related Identifiers

CVE-2026-41927

Affected Products

Wifi Extender Wdr201A

References · 8

• 🔥 https://mstreet97.github.io/security-research/iot/vulnerability-disclosure/ai-assisted-research/cybersecurity/cve/2026/05/04/Teaching_the_Machine_Where_to_Look.html · Exploit
• https://nvd.nist.gov/vuln/detail/CVE-2026-41927 · Security Note
• https://t.me/CVEtracker/52673 · Telegram Post
• https://made-in-china.com/showroom/yeapook/#:~:text=Established%20in%202015.%2CDistrict%2C%20Shenzhen%2C%20Guangdong%2C%20China · Note
• https://twitter.com/VulmonFeeds/status/2051490691709071619 · Twitter Post
• https://vulncheck.com/advisories/wdr201a-wifi-extender-stack-based-buffer-overflow-via-firewall-cgi · Note
• https://twitter.com/infoflowcloud/status/2051405575557140692 · Twitter Post
• https://twitter.com/CVEnew/status/2051403821901906110 · Twitter Post